[Campbell Biology P.722] Based on the 'Study Tip' and associated diagram, what is the earlie... | Practice Question

Based on the 'Study Tip' and associated diagram, what is the earliest known biochemical evidence of animal life mentioned, and approximately how long ago did it occur?

  • A: Ediacaran biota, occurring around 600 million years ago.
  • B: Sediments containing steroids from sponges, occurring 710 million years ago.
  • C: Cambrian explosion, occurring around 540 million years ago.
  • D: Colonization of land by vertebrates, occurring much more recently.

Explanation

The 'Study Tip' section explicitly mentions 'First biochemical evidence of animals: Sediments containing steroids from sponges' and the accompanying timeline diagram points to '710 million years ago mya ' for this event.